The diagnosis of chronic pancreatitis continues to present difficulties. The nonspecific nature of the symptomatology, its low prevalence and the limited value of morphological and functional tests in the early stages are the most common causes of delay in diagnosis. Our aim was to analyze the most significant clinical manifestations and the diagnostic features of chronic pancreatitis, distinguishing between alcoholic and nonalcoholic etiologies. We studied 158 patients, 136 (86.1%) with alcoholic and 22 (13.9%) with nonalcoholic chronic pancreatitis. The initial symptomatology, the age at diagnosis, the delay in diagnosis from the onset of the clinical signs and the type of diagnosis (incidental or suspected) were considered for each patient. Men predominated in both the alcoholic and the nonalcoholic pancreatitis groups (97.8% and 68.2%, respectively). The mean ages at onset and diagnosis were 38 and 50.6 years, respectively, in alcoholic chronic pancreatitis and 44 and 55 years in the nonalcoholic group; the differences between the two parameters were statistically significant. The most common clinical signs in alcoholic chronic pancreatitis were abdominal pain (81.6%) and episodes of acute pancreatitis (64%), while patients with nonalcoholic pancreatitis presented abdominal pain (59%), diarrhea (40.9%) and weight loss (36.4%). The delay in diagnosis from the onset of the clinical manifestations was 5.8 years (6.1 years in alcoholic and 4.3 years in nonalcoholic pancreatitis. The diagnosis was incidental in 34% of cases of alcoholic chronic pancreatitis and in 50% of cases in the nonalcoholic group.